A major cause of congestion and wasted travel time, especially in business districts, is parking search. That is, people often ``circle around'' looking for a good parking space. This causes congestion both because it adds to the number of vehicles on the road at any point in time and because people tend to drive fairly slowly when searching. One way to alleviate congestion of this kind is using TIDE technologies.

First, the Center is considering ways in which sensing technologies can be used to determine the current capacity of a parking facility (be it a parking lot, a garage, or on-street parking). Specific attention is being given to ingress/egress detectors (e.g., infrared detectors) and area-wide detectors (e.g., video image processing). Ingress/egress detectors simply count the number of vehicles entering and exiting a facility and use the difference between the number of entering and exiting vehicles as the current occupancy. Area-wide detectors attempt to determine the number of vehicles in their field of vision directly. Obviously, depending on the circumstances, one or both types of sensors may be desirable/required.

Second, the Center is developing technologies that can be used to make this information available to vehicles as they approach the facility (e.g., using in-vehicle computers, cellular telephones, pagers, and variable message signs) and to determine good/optimal routes to available spaces. Technologies along the entire cost/value spectrum are being considered.

Third, the Center is developing technologies for forecasting the demand for, and availability of, parking spaces. This will enable the routing technologies to use predicted, rather than current, conditions and should enable routing decisions to be made while the vehicle is farther from its destination.

Finally, the Center is developing both hardware (similar to those being developed for electronic toll collection) and software technologies that enable drivers to reserve particular parking spaces while on route and, where appropriate, pay for the spaces electronically. These efforts are focused on technologies that are appropriate for limited access parking facilities rather than on-street parking.

This application of these technologies will be field-tested at one or more parking facilities in New Jersey. Possible test sites include Newark airport, the NJ Center for the Performing Arts, and commercial/university parking facilities in Princeton and Newark.